Preparation of some new benzo[d]thiazole derivatives

Abstract

In this work, four new benzo[d]thiazole derivatives were synthesized successfully from vanillin. Nitration of vanillin gave nitrovanillin followed by cyclization reaction with o-aminothiophenol under microwave irradiation in 4 minutes to give nitroaromatic compound 3. The reduction to convert the nitro group to amino group was optimized. It was found that Fe/ con. HCl in ethanol was the best condition for this case about both yield (95 %) and simple procedure to give compound 4 as a salt. Acetylation occurs at both phenolic hydroxyl group and amino group of the salt 4 to form N,O-acetyl compound 5. Under mild hydrolysis 5 produces N-acetyl compound 6. The structures of these compounds were established by IR, 1 H and 13 C NMR and mass spectral analyses.

Synthesis of 5-nitrovanillin in low temperature as cyanide anion sensor

“…Nitration of vanillin at position 6 was carried out by Yadav et al, Through acetyl vanillin intermediates using DCM, acetic anhydride, and dry pyridine [7,8]; and Rakshit et al, [9] carried out the nitration of vanillin via the o-Bn-vanillin intermediate. 5-nitrovanilin compounds can also be synthesized in cold conditions using HNO3 and acetic acid [10]. The 5-nitrovanillin synthesis in this study was carried out using a combination of these methods.…”